Lifting mechanism



Nov. 21, 1950 o. c. K. HUTCHINSON 2,530,771

LIFTING MECHANISM Filed June 18, 1945 2 Sheets-Sheet 1 INVEN TOR Nov. 21, 1950 o, c. HUTCHINSON 2,530,771

LIFTING MECHANISM Filed June 18, 1945 2 Sheets-Sheet 2 INVENTOR Patented Nov. 21, 1950 UNITED STATES PATENT OFFICE LIFTING MECHANISM Oliver 0. Kemp Hutchinson, Alton, Ill.

Application June 18, 1945, Serial No. 600,166

8 Claims.

i This invention relates to handling mechanism for barrel-like vessels and other relatively round bulging objects. More particularly the invention relates to an improved mechanism for handling crucibles when filled with molten metal.

In the art of handling molten metal as practiced heretofore, the metal is contained in crucibles or pots, said crucibles being formed of plastic materials, such as fire clay, silicon-carbide mixtures, etc. Efficiency in melting and handling often requires that the size of crucibles be relatively large, resulting in a gross weight 01 several hundred pounds. The mechanical strength of such crucibles is relatively low and under the influence of the high temperatures necessary to sustain proper fluidity of the metal Within the crucible, the strength is often still further reduced.

It is found that under repeated use, crucibles fail by cracking of the side walls, or by breaking through in spots, permitting the molten metal to flow out. In some instances this becomes hazardous to workmen. It is further found that the mechanisms heretofore provided for lifting and handling crucibles are in part responsible for premature failures.

In the art as practiced heretofore, the mechanism for lifting crucibles as from the melting furnaces, has most generally consisted essentially of a pair of hinged tongs, the lower arms of which are shaped to conform approximately to the side walls of the pot, the upper arms being provided with an eye which engages a lifting hook, as of a hoisting mechanism. In all such devices, the hinged tongs must necessarily exert sufiicient compression against the side walls of the pot to permit lifting the gross weight. The leverage action is such that this compression force is necessarily relatively high. This results in crushing or distorting the side walls of the pot, and ultimately develops cracks or weakened spots which break through.

Such a disadvantageous condition is aggravated by the fact that the space available between the crucible and the side walls of the melting furnace in which the crucible is heated is ordinarily restricted, which in turn limits the size and hence the strength of the lower formed arms of the lifting tongs. Under the intense temperature conditions within the furnace, these formed arms lose their shape, which in turn causes them to set up excessive pressures near the top rim of the pot.

Other types of mechanism proposed heretofore for handling such vessels have had inherent disadvantages rendering them still lesssuitable for the purpose.

A primary object of this invention is to provide an improved mechanism for efficiently handling such round bulging vessels without the disadvantages attending all such prior devices.

Another object of this invention is to provide a lifting mechanism which will avoid subjecting the side walls of such vessels to excessive pressures. Another object is to provide a lifting mechanism which will not subject the upper wall sections of a metal-holding crucible to pressure. Another object is to provide a lifting mechanism which will not deform in a manner which will subject the upper walls of such a crucible to pressure. Another object is to increase the number of times such a crucible can be used before breakage of the side walls occurs. Further objects and advantages will appear from the following description taken in connection with the accompanying drawing, in which- Figure 1 is a front elevation of a mechanism illustrating one embodiment of this invention and Figure 2 is a side elevation of the mechanism, and

Figure 3 is a plain view of the mechanism, partly in section, and V Figure 4 is an elevation showing a section taken at IV-IV of Figure 3 with the mechanism in a position unengaged with the vessel, and

Figure 5 is an elevation showing a section taken at IV--IV of Figure 3 with the mechanism in a position engaging and lifting the vessel.

The above objects and advantages are accomplished in accordance with this invention by the provision of a novel mechanism including a support member or ring of larger diameter than the vessel to be lifted with means for inserting wedge members between the ring and vessel and with means for lifting the support ring while the vessel is supported by the wedge members intermediate the vessel and ring,

Referring to the accompanying drawing, Figures 1 and 2, the support member or ring 2 having a diameter greater than the vessel l is carried by a frame formed of the two hanger members 8 connected at the top by a yoke or trunnion l9 which is adapted to receive a hoisting mechanism hook. The wedge members or blocks 4 are movably attached to a carrier ring 3 supported by two arms or links 9, which are connected at their top ends by hinge pins 22 to levers l3 having grips or handles l6. Levers I3 are movably attached to guide bars I5 by pivot pin I4, which extends through both guides I5. The guide bars I5 are attached at one end to hanger members 8 and are further strengthened and braced by means of tubular spacer members I! surrounding the pivot pin I4 and by means of brace members I8 attached at the lower ends to the hanger members 8 and at the upper ends to pivot pin I4. Cross bars I2 and 26 serve to brace and reinforce the hangers and in addition bar I2 may be so located as to serve as a stop when the mechanism is lowered over the vessel. Stop pins I6 rigidly fixed on hangers 8 passing through slots II in the arms 9 tend to limit the movement of carrier ring 3 with respect to support ring 2 and likewise guide the position of the lower end of arms 9.

Referring to Figures 3, 4, and 5, wedge blocks 4 are movably attached to ring 3 by means of bolts 1 fitting loosely in holes H in the members 4. The upper ends 5 of members 4 are turned over carrier ring 3 to limit the side movement of member 4. The support ring 3 may have an inner surface contour suitable for receiving the Wedge blocks 4, or may include suitably contoured pads such as at 6 positioned about the ring 3 to receive the wedge blocks 4. As illustrated in Figure 4, the ring 3 is in raised position permitting the series of wedge blocks 4 to swing outward in disengaging position so as to clear the bulged wall of the vessel I as support ring 2 is lowered over the vessel. Stop pin ID in slot II limits the upward movement of ring 3 so that the blocks 4 remain in contact with the up er edge of the pad portions 6 of ring 2 in position to be easily lowered between the pad portions 6 and vessel I. Support ring 2 is in its lowest position with stop bar I2 resting on top of the vessel I.

As illustrated in Figure 5, the mechanism is in a position lifting the vessel I. Ring 3 has been lowered so" that wedge blocks 4 are in position between pads 6 and vessel I, and the support ring 2 has been raised to the point at which the blocks 4 engage the walls of vessel I and are firmly wedged between the vessel I and support ring '2, so that the vessel I is readily lifted by further raising the support ring 2.

In operation the handle or guide bars I5 are used toguide the lifting mechanism when it is suspended froma hoist. In lifting a crucible, the handles or grips I6 of levers I3 are depressed, which raises the links 9 carrying ring 3 and permits blocks 4 to swing-outward on the upper-edge of pad portions 6. The depression of handles I6 is stopped by stop pin III in slot 9. .The mechanism with the handles I6 maintained depressed is then lowered by means of a hoist connected at I9 over the crucible until stop bar I2 rests on the vessel, as illustrated in Figure 4. Handles I6 are then released permitting ring 3 to drop until pin Illrests in the upper end of slot II with blocks 4 between vessel I and pads 6. The mechanism is then raised by means of the hoist with the result that blocks 4 engage the walls of the vessel I and bear firmly against the pads 6 as illustrated in Figure 5. When the lifting operation is completed, the mechanism is removed from the crucible merely by lowering the mechanism until stop bar I2 rests on top the vessel, depressing handles I6, and raising the mechanism off the vessel by means of the hoist. It is only necessary to lower the ring 2 to a position where the diameter of the vessel is small enough to permit elevation of blocks 4 by depression of handles I6 in order to release the mechanism from the vessel 4 and permit its removal. Bar I2 facilitates such positioning of the ring 2.

In the mechanism, the lifting force is transmitted from a hoisting mechanism hook which engages the yoke I9, through the two hanger members 8 which are rigidlyattached to the main support ring 2, and the weight of the crucible l is supported by the wedge blocks 4, which engage the side walls at points near the bottom of the crucible I and which bear firmly against the support ring 2.

In the above specific embodiments, the invention has been described with regard to round vessels bulging near the center. It should be understood that the invention is likewise applicable to any such round vessel having a smaller diameter toward the bottom, for instance with the bulge or largest diameter at the top. The invention is likewise applicable to other bulging vessels which are not round, for instance having an elliptical, or triangular, or square or etc.,- cross section, in which case the rings 2 and 3 may have the same shape as the vessel, i. e. elliptical, or triangular, or square, or etc., so that the ring 2 when lowered about the vessel will clear the side walls" by a uniform distance. Pad portions 6 may likewise be employed with an annular ring 2 with the pad portions being of different thickness to conform to the contour of such vessels. The invention accordingly has a wide field of application and utility.

From the above description it may be seen that this mechanism supports such vessels in a manner which does not set up excessive pressure in the walls and that the mechanism does not operate to set up pressures on the upper wall sections. Likewise, in contrast to prior devices of the tong type, no excessive strain or leverage actions can develop which will cause deformation of the mechanism in a manner which will result in abnormal and excessive Strains on the vessel walls.

Having thus described the invention in detail, what is claimed and desired to secure by Letters Patent is:

1. Carrying mechanism for a vessel having bulging sidewalls, comprising in combination a support ring of greater diameter than said vessel, a plurality of wedge members, hanger means carrying said ring,.a support for said wedge members movably mounted on said hanger means, means for inserting said wedge members between said ringand said vessel in position for engaging the bulging sidewalls of said vessel while bearing against said ring, stop means on said hanger for limiting the movement of the wedge members relative to the support ring, and means for connecting said hanger members to a hoist.

2 Carrying mechanism for a vessel having bulging sidewalls, comprising in combination a support member adapted to be positioned about said vessel, hanger means rigidly connected to said support member, a carrier member supported by said hanger means, a plurality of wedge members movably connected to said carrier member, means for inserting said wedge members between said support member and said vessel in position for engaging the bulging sidewalls of said vessel while bearing against said ring, stop means on said hanger for limiting the movement of the wedge members relative to the support member, and means for connecting said hanger means to a hoist.

3. Carrying mechanism for a vessel having bulging sidewalls, comprising in combination a support ring having a diameter greater than said vessel, hanger means rigidly connected to said support ring, a carrier ring above said upport ring mounted for vertical movement on said hanger means, "a plurality of wedge members hanging from said carrier ring, means for raising said carrier ring and lowering said carrier ring to insert said wedge members between said vessel and said support ring in position for engaging the bulging sidewalls of said vessel while bearing against said support ring, stop means on said hanger for limiting the movement of the wedge members relative to the support ring, and means for connecting said hanger means to a hoist.

4. Carrying mechanism for a vessel having bulging sidewalls comprising in combination a support ring having a diameter greater than said vessel and adapted to be lowered about said vessel, hanger means rigidly connected to said support ring, a carrier ring above said support ring mounted for vertical movement on said hanger means, stop means for limiting the vertical movement of said carrier ring, a plurality of wedge members hanging from said carrier ring, lever means for raising said carrier ring and for lowering said carrier ring to insert said wedge members between said vessel and said support ring in position for engaging the bulging sidewalls of said vessel while bearing against said support ring, stop means on said hanger for limiting the movement of the wedge members relative to the support ring and means for connecting said hanger means to a hoist.

5. Carrying mechanism for a vessel having bulging sidewalls comprising in combination a support ring having a diameter greater than said vessel and adapted to be lowered about said vessel, hanger means rigidly connected to said support ring, a carrier ring above said support ring mounted for Vertical movement on said hanger means, stop means for limiting the vertical movement of said carrier ring, a plurality of wedge members hanging from said carrier ring, lever means for raising said carrier ring and for lowering said carrier ring to insert said wedge members between said vessel and said support ring in position for engaging the bulging sidewalls of said vessel while bearing against said support ring, means on said hanger means for engaging the top of said vessel and fixing the lowest position of said support ring about said vessel, guide bars rigidly connected to said hanger means, and means for connecting said hanger means to a hoist.

6. Carrying mechanism for a vessel havin bulging side walls comprising a support ring adapted to be positioned about said vessel, wedge members adapted to be inserted between said ring and said vessel, means for inserting said wedge members between said ring and vessel, means for fixing the lowest position of said ring about said vessel, means for lifting said ring, and guide means for said ring.

7. Carrying mechanism for a vessel having bulging side walls comprising a frame having guide means, a support ring rigidly attached at the bottom of said frame and adapted to be lowered about and below the bulging side walls of the vessel, a plurality of spaced wedge members mounted for vertical movement on said frame and adapted to be inserted between said ring and vessel, means mounted on said guide means for el fecting vertical movement of said wedge members relative to said support ring, means limiting the movement of said wedge members relative to said support ring, and means for lifting said frame.

3. Carrying mechanism for a vessel having bulging side walls, comprising in combination a support member adapted to be positioned about said vessel, wedge members adapted for movement into position between the sidewalls 0f the vessel and said support member and adapted to engage and support said vessel while bearing against said support member, hanger means carrying said support member, a support for said wedge members movably mounted on said hanger means, means for moving said wedge member support, means on said hanger means engaging the top of the vessel and fixing the lowest position of said support member, and means for connecting said hanger means with a hoist.

O. C. KEMP HUTCI-IINSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 927,022 Blackham July 6, 1909 976,042 Carr Nov. 15, 1910 1,173,445 Lohr Feb. 29, 1916 1,332,234 Raidt Mar. 2, 1920 1,473,013 Clark Nov. 6, 1923 1,555,379 Moody Sept. 29, 1925 

